Remove SK_RESOLVE_FILTERS_BEFORE_RESTORE flag

[lhkbob]

Update SaveLayerConsolidation unit tests to allow 1px differences due to rounding differences when Skia elides image filter passes and can calculate the CF and opacity in full float without an intermediate conversion to 8-bit color.

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[flutter-dashboard[bot]]

This pull request has been changed to a draft. The currently pending flutter-gold status will not be able to resolve until a new commit is pushed or the change is marked ready for review again.

[goderbauer]

(triage) I spoke to @lhkbob last week and they said they plan to come back to this PR soon.

[auto-submit[bot]]

auto label is removed for flutter/engine/49563, due to This PR has not met approval requirements for merging. The PR author is not a member of flutter-hackers and needs 1 more review(s) in order to merge this PR.

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[auto-submit[bot]]

auto label is removed for flutter/engine/49563, due to - The status or check suite Linux local_engine_builds has failed. Please fix the issues identified (or deflake) before re-applying this label.